Disclosed are a series of heteroaryl-β-alanine derivatives, compositions containing them, processes for their preparation and their use in medicine....http://www.google.com.au/patents/US20020086882?utm_source=gb-gplus-sharePatent US20020086882 - Regulates immune and inflammatory responses by binding to alpha 4 integrin, also know as Very Late Antigen; antiinflammatory agent

Regulates immune and inflammatory responses by binding to alpha 4 integrin, also know as Very Late Antigen; antiinflammatory agentUS 20020086882 A1

Abstract

Disclosed are a series of heteroaryl-β-alanine derivatives, compositions containing them, processes for their preparation and their use in medicine.

Images(42)

Claims(8)

What is claimed is:

1. A compound of the formula:

wherein

Ar1 is an aromatic or heteroaromatic group;

R1, R2, R3, R4 and R5 which may be the same or different is each an atom or group —L2(Alk3)tL3(R7)u in which L2 and L3 which may be the same or different is each covalent bond or a linker atom or group, t is zero or the integer 1, u is an integer 1, 2 or 3, Alk3 is an aliphatic or heteroaliphatic chain and R7 is a hydrogen or halogen atom or a group selected from alkyl, —OR8, where R8 is a hydrogen atom or an optionally substituted alkyl group, —SR8, —NR8R9, where R9 is as just defined for R8 and may be the same or different, —NO2, —CN, —CO2R8, —SO3H, —SOR8, —SO2R8, —OCO2R8, —CONR8R9, —OCONR8R9, —CSNR8R9, —COR8, —OCOR8, —N(R8)COR9, —N(R8)CSR9, —SO2N(R8)(R9), —N(R8)SO2R9, —N(R8)CON(R9)(R10), where R10 is a hydrogen atom or an optionally substituted alkyl group, —N(R8)CSN(R9)(R10) or —N(R8)SO2N(R9)(R10);

Alk1 is an optionally substituted aliphatic or heteroaliphatic chain;

L1 is a covalent bond or a linker atom or group;

Alk2 is a straight or branched alkylene chain;

m is zero or an integer 1;

R6 is a hydrogen atom or a methyl group;

r is zero or the integer 1;

R is a carboxylic acid (—CO2H) or a derivative thereof;

Ra is a hydrogen atom or a methyl group;

Ar2 is an optionally substituted aromatic or heteroaromatic group;

B is a nitrogen containing heteroaryl group;

and the salts, solvates, hydrates and N-Oxides thereof.

2. A compound of the formula:

wherein R, Ra, R4, R5, R6, Alk2, B, m and Ar2 are as defined above and R1′ and R2′ are independently selected from the group consisting of hydrogen, alkyl, substituted alkyl, alkenyl, substituted alkenyl, aryl, cycloalkyl, substituted cycloalkyl, heterocyclic, heteroaryl or R1′ and R2′, together with the nitrogen atom to which they are attached, are joined to form an optionally substituted heterocyclic ring; and the salts, solvates, hydrates and N-oxides thereof.

3. The compound according to claim 2 wherein R1′ and R2′ are independently selected from the group consisting of hydrogen, alkyl, substituted alkyl, alkenyl, substituted alkenyl, cycloalkyl, substituted cycloalkyl, or R1 and R2, together with the nitrogen atom to which they are attached, are joined to form an optionally substituted heterocyclic ring provided that said substituted alkyl, substituted alkenyl and substituted cycloalkyl do not carry an aryl, substituted aryl, heteroaryl or substituted heteroaryl group.

4. A compound of the formula:

wherein

Ar1 is an aromatic or heteroaromatic group;

R1, R2, R3, R4 and RS which may be the same or different is each an atom or group —L2(Alk3)tL3(R7)u in which L2 and L3 which may be the same or different is each a covalent bond or a linker atom or group, t is zero or the integer 1, u is an integer 1, 2 or 3, Alk3 is an aliphatic or heteroaliphatic chain and R7 is a hydrogen or halogen atom or a group selected from alkyl, —OR8, where R8 is a hydrogen atom or an optionally substituted alkyl group, —SR8, —NR8R9, where R9 is as just defined for R8 and may be the same or different, —NO2, —CN, —CO2R8, —SO3H, —SOR8, —SO2R8, —OCO2R8, —CONR8R9, —OCONR8R9, —CSNR8R9, —COR8, —OCOR8, —N(R8)COR9, —N(R8)CSR9, —SO2N(R8)(R9), —N(R8)SO2R9, —N(R8)CON(R9)(R10), where R10 is a hydrogen atom or an optionally substituted alkyl group, —N(R8)CSN(R9)(R10) or —N(R8)SO2N(R9)(R10);

Alk1 is an optionally substituted aliphatic or heteroaliphatic chain;

L1 is a covalent bond or a linker atom or group;

Alk2 is a straight or branched alkylene chain;

m is zero or an integer 1;

R6 is a hydrogen atom or a methyl group;

r is zero or the integer 1;

R is a carboxylic acid (—CO2H) or a derivative thereof;

Ra is a hydrogen atom or a methyl group;

Ar2 is selected from the group consisting of moieties of formula IIIa, IIIc, IIId, IIIe and IIIf:

5. A pharmaceutical composition comprising a pharmaceutically acceptable excipient and an effective amount of a compound according to any of claims 1-4.

6. A method for binding VLA-4 in a biological sample which method comprises contacting the biological sample with a compound according to any of claims 1-4 under conditions wherein said compound binds to VLA-4.

7. A method for treating an inflammatory condition in a mammalian patient which condition is mediated by VLA-4 which method comprises administering to said patient a therapeutically effective amount of a pharmaceutical composition of claim 6.

[0001] This application claims the benefit of U.S. Ser. No. 60/220,128, filed Jul. 21, 2000, which is incorporated by reference in its entirety.

[0002] This invention relates to a series of heteroaryl-β-alanine derivatives, to compositions containing them, to processes for their preparation, and to their use in medicine.

[0003] Over the last few years it has become increasingly clear that the physical interaction of inflammatory leukocytes with each other and other cells of the body plays an important role in regulating immune and inflammatory responses [Springer, T A. Nature, 346,425, (1990); Springer, T. A. Cell 76, 301, (1994)]. Many of these interactions are mediated by specific cell surface molecules collectively referred to as cell adhesion molecules.

[0004] The adhesion molecules have been sub-divided into different groups on the basis of their structure. One family of adhesion molecules which is believed to play a particularly important role in regulating immune and inflammatory responses is the integrin family. This family of cell surface glycoproteins has a typical non-covalently linked heterodimer structure. At least 14 different integrin alpha chains and 8 different integrin beta chains have been identified [Sonnenberg, A. Current Topics in Microbiology and Immunology, 184, 7, (1993)]. The members of the family are typically named according to their heterodimer composition although trivial nomenclature is widespread in this field. Thus the integrin termed α4β1 consists of the integrin alpha 4 chain associated with the integrin beta I chain, but is also widely referred to as Very Late Antigen 4 or VLA4. Not all of the potential pairings of integrin alpha and beta chains have yet been observed in nature and the integrin family has been subdivided into a number of subgroups based on the pairings that have been recognized [Sonnenberg, A. ibid.]

[0005] The importance of cell adhesion molecules in human leukocyte function has been further highlighted by a genetic deficiency disease called Leukocyte Adhesion Deficiency (LAD) in which one of the families of leukocyte integrins is not expressed [Marlin, S. D. et al J. Exp. Med. 164, 855 (1986)]. Patients with this disease have a reduced ability to recruit leukocytes to inflammatory sites and suffer recurrent infections which in extreme cases may be fatal.

[0006] The potential to modify adhesion molecule function in such a way as to beneficially modulate immune and inflammatory responses has been extensively investigated in animal models using specific monoclonal antibodies that block various functions of these molecules [e.g. Issekutz, T. B. J. Immunol. 3394, (1992); Li, Z. et al (Am. J. Physiol. 263, L723, (1992); Binns; R. M. et al J. Immunol. 157, 4094, (1996)]. A number of monoclonal antibodies which block adhesion molecule function are currently being investigated for their therapeutic potential in human disease.

[0007] One particular integrin subgroup of interest involves the α4 chain which can pair with two different beta chains β1 and β7 [Sonnenberg, A. ibid]. The α4β1 pairing occurs on many circulating leukocytes (for example lymphocytes, monocytes and eosinophils) although it is absent or only present at low levels on circulating neutrophils. α4β1 binds to an adhesion molecule (Vascular Cell Adhesion Molecule-1 also known as VCAM-1) frequently up-regulated on endothelial cells at sites of inflammation [Osborne, L. Cell, 62, 3, (1990)]. The molecule has also been shown to bind to at least three sites in the matrix molecule fibronectin [Humphries, M. J. et al. Ciba Foundation Symposium, 189, 177, (1995)]. Based on data obtained with monoclonal antibodies in animal models it is believed that the interaction between α4β1 and ligands on other cells and the extracellular matrix plays an important role in leukocyte migration and activation [Yednock, T. A. et al, Nature, 356, 63, (1992); Podolsky, D. K. et al. J. Clin. Invest. 92, 373, (1993); Abraham, W. M. et al. J. Clin. Invest. 93, 776, (1994)].

[0008] The integrin generated by the pairing of α4 and β7 has been termed LPAM-1 [Holzmann, B and Weissman, I. EMBO J. 8, 1735, (1989)] and like α4β1, binds to VCAM-1 and fibronectin. In addition, a4β7 binds to an adhesion molecule believed to be involved in the homing of leukocytes to mucosal tissue termed MAdCAM-I [Berlin, C. et al, Cell, 74, 185, (1993)]. The interaction between α4β1 and MAdCAM-1 may also be important at sites of inflammation outside of mucosal tissue [Yang, X-D. et al, PNAS, 91, 12604 (1994)].

[0009] Regions of the peptide sequence recognised by α4β1 and α4β1 when they bind to their ligands have been identified. α4β1 seems to recognise LDV, IDA or REDV peptide sequences in fibronectin and a QIDSP sequence in VCAM-1 [Humphries, M. J. et al, ibid]whilst α4β1 recognises a LDT sequence in MAdCAM-1 [Briskin, M. J. et al, J. Immunol. 156, 719, (1996)]. There have been several reports of inhibitors of these interactions being designed from modifications of these short peptide sequences [Cardarelli, P. M. et al J. Biol. Chem. 269, 18668, (1994); Shroff, H. N. Bioorganic. Med. Chem. Lett. 6, 2495, (1996); Vandlerslice, P. J. Immunol. 158, 1710, (1997)]. It has also been reported that a short peptide sequence derived from the α4β1 binding site in fibronectin can inhibit a contact hypersensitivity reaction in a trinitrochlorobenzene sensitised mouse [Ferguson, T. A. et al, PNAS 88, 8072, (1991)].

[0010] Since the alpha 4 subgroup of integrins are predominantly expressed on leukocytes their inhibition can be expected to be beneficial in a number of immune or inflammatory disease states. However, because of the ubiquitous distribution and wide range of functions performed by other members of the integrin family it is very important to be able to identify selective inhibitors of the alpha 4 subgroup.

[0011] We have now found a group of compounds which are potent and selective inhibitors of α4 integrins. Members of the group are able to inhibit ix4 integrins such as α4β1 and/or (α4β7 at concentrations at which they generally have no or minimal inhibitory action on a integrins of other subgroups. The compounds are thus of use in medicine, for example in the prophylaxis and treatment of immune or inflammatory disorders as described hereinafter.

[0012] Thus according to one aspect of the invention we provide a compound of formula (1)

[0013] wherein

[0014] Ar1 is an aromatic or heteroaromatic group;

[0015] R1, R2, R3, R4 and R1 which may be the same or different is each an atom or group

[0016] —L2(Alk3)tL3(R7)u in which L2 and L3 which may be the same or different is each a covalent bond or a linker atom or group,

[0017] t is zero or the integer 1,

[0018] u is an integer 1, 2 or 3,

[0019] Alk3 is an aliphatic or heteroaliphatic chain and R7 is a hydrogen or halogen atom or a group selected from alkyl, —OR8, where R8 is a hydrogen atom or an optionally substituted alkyl group, —SR8, —NR8R9, where R9 is as just defined for R8 and may be the same or different, —N02, —CN, —C02R8, —SO3H, —SOR8, —SO2R8 —OC02R8, —CONR8R9, —OCONR8R9, —CSNR8R9, —COR8, —OCOR8, —N(R8)COR9, —N(R8)CSR9, —SO2N(R8)(R9), —N(R8)SO2R9, —N(R8)CON(R9) (R10), where R10 is a hydrogen atom or an optionally substituted alkyl group, —N(R8)CSN(R9)(R10) or —N(R8)SO2N(R9)(R10);

[0020] Alk1 is an optionally substituted aliphatic or heteroaliphatic chain;

[0021] L1 is a covalent bond or a linker atom or group;

[0022] Alk2 is a straight or branched alkylene chain;

[0023] m is zero or an integer 1;

[0024] R6 is a hydrogen atom or a methyl group;

[0025] r is zero or the integer 1;

[0026] R is a carboxylic acid (—CO2H) or a derivative thereof;

[0027] Ra is a hydrogen atom or a methyl group;

[0028] Ar2 is an optionally substituted aromatic or heteroaromatic group;

[0029] B is a nitrogen containing heteroaryl group;

[0030] and the salts, solvates, hydrates and N—Oxides thereof

[0031] Another class of compounds within the scope of this invention include compounds of formula (2)

[0032] wherein R, Ra, R4, R5, R6, Alk2, B, m and Ar are as defined above and R1 and R2 are independently selected from the group consisting of hydrogen, alkyl, substituted alkyl, alkenyl, substituted alkenyl, aryl, cycloalkyl, substituted cycloalkyl, heterocyclic, heteroaryl or R1 and R2, together with the nitrogen atom to which they are attached, are joined to form an optionally substituted heterocyclic ring; and the salts, solvates, hydrates and N-oxides thereof.

[0033] In one preferred embodiment, R1 and R2 are independently selected from the group consisting of hydrogen, alkyl, substituted alkyl, alkenyl, substituted alkenyl, cycloalkyl, substituted cycloalkyl, or R1 and R2, together with the nitrogen atom to which they are attached, are joined to form an optionally substituted heterocyclic ring provided that said substituted alkyl, substituted alkenyl and substituted cycloalkyl do not carry an aryl, substituted aryl, heteroaryl or substituted heteroaryl group.

[0034] Preferably, in the compounds of this invention, Ar2 is selected from the group consisting of moieties of formula IIIa, IIIc, IIId, IIIe or IIIf:

[0044] It will be appreciated that compounds of formula (1) may have one or more chiral centers, and exist as enantiomers or diastereomers. The invention is to be understood to extend to all such enantiomers, diastereomers and mixtures thereof, including racemates. Formula (1) and (2) and the formulae hereinafter are intended to represent all individual isomers and mixtures thereof, unless stated or shown otherwise.

[0045] In the compounds of formula (1), derivatives of the carboxylic acid group R include carboxylic acid esters and amides. Particular esters and amides include —CO2Alk5 groups and —CONR8R9 groups as described herein.

[0046] In general, the substituents R1, R2 and R1 in compounds of the invention may be positioned on any available carbon atom, or, when present, nitrogen atom in the aromatic or heteroaromatic group represented by Ar1.

[0047] When Alk1 is present in compounds of formula (1) as an optionally substituted aliphatic chain it may be an optionally substituted C1-10 aliphatic chain. Particular examples include optionally substituted straight or branched chain C1-6 alkyl, C2-6 alkenyl, or C2-6 alkynyl chains.

[0048] Heteroaliphatic chains represented by Alk1 include the aliphatic chains just described but with each chain additionally containing one, two, three or four heteroatoms or heteroatom-containing groups. Particular heteroatoms or groups include atoms or groups L4 where L4 is as defined above for L1 when L1 is a linker atom or group. Each L4 atom or group may interrupt the aliphatic chain, or may be positioned at its terminal carbon atom to connect the chain to an adjoining atom or group.

[0049] Particular examples of aliphatic chains represented by Alk1 include optionally substituted —CH2—, —CH2CH2—, —CH(CH3)—, —C(CH3 )2—, —(CH2)2CH2—, —CH(CH3 )CH2—, —(CH2 )3 CH2—, —CH(CH3 )CH2CH2—, —CH2CH(CH3) CH2—, —C(CH3)2CH2—, —(CH2)4CH2—, —(CH2),CH2—, —CHCH—, —CHCHCH2—, —CH2CHCH—, —CHCHCH2CH2—, —CH2CHCHCH2—, —(CH2)2CHCH—, —CC—, —CCCH2—, —CH2CC—, —CCCH2CH[2—, —CH2CCCH2—, or —(CH2)2CC— chains. Where appropriate each of said chains may be optionally interrupted by one or two atoms and/or groups L4 to form an optionally substituted heteroaliphatic chain. Particular examples include optionally substituted —L4CH2—, —Ch2L4CH2—, —L4(CH2)2—, —CH2L4(CH2)2—, (CH2)2L4CH2—, —L4(CH2)3— and —(CH2)2L4(CH2)2— chains. The optional substituents which may be present on aliphatic or heteroaliphatic chains represented by Alk1 include one, two, three or more substituents where each substituent may be the same or different and is selected from halogen atoms, e.g. fluorine, chlorine, bromine or iodine atoms, or C1-6 alkoxy, e.g. methoxy or ethoxy, thiol, C1-6 alkylthio e.g. methylthio or ethylthio, amino or substituted amino groups. Substituted amino groups include —NHR12 and —N(R12)2 groups where R12 is an optionally substituted straight or branched alkyl group as defined below for R11. Where two R12 groups are present these may be the same or different. Particular examples of substituted chains represented by Alk1 include those-specific chains just described substituted by one, two, or three halogen atoms such as fluorine atoms, for example chains of the type —CH(CF3)—, —C(CF3)2— —CH2CH(CF3)—, —CH2C(CF3)2—, —CH(CF3)— and —C(CF3)2CH2.

[0050] Alk2 in the compounds of the invention may be for example a straight or branched C1-3 alkylene chain. Particular examples include —CH2—, —CH(CH3)— and —(CH2)2—.

[0051] When in the compounds of formula (1) L1, L2 and/or L3 is present as a linker atom or group it may be any divalent linking atom or group. Particular examples include —O— or —S— atoms or —C(O)—, —C(O)O—, —OC(O)—, —C(S)—, —S(O)—, —S(O)2—, —N(R11)—, where R11 is a hydrogen atom or an optionally substituted alkyl group, —CON(R11)—, —OC(O)N(R11)—, —CSN(R11)—, —N(R11)CO—, —N(R11)C(O)O—, —N(R11)CS—, —S(O)2N(R11)—, —N(R11)S(0)2—, —N(R11) CON(R11), —N(R11)CSN(R11)—, or —N(R11)SO2N(R11)— groups. Where the linker group contains two R11 substituents, these may be the same or different.

[0052] When R7, R8, R9, R10 and/or R11 in the compounds of formula (1) is an alkyl group it may be a straight or branched C1-6alkyl group, e.g. a C1-3 alkyl group such as a methyl or ethyl group. Optional substituents which may be present on such groups include for example one, two or three substituents which may be the same or different selected from halogen atoms, for example fluorine, chlorine, bromine or iodine atoms, or hydroxy or C1-6alkoxy e.g. methoxy or ethoxy groups.

[0053] When Alk3 is present in the compounds of formula (1) as an aliphatic or heteroaliphaiic chain it may be for example any of the above-mentioned C1-10 aliphatic or heteroaliphatic chains described for Alk1.

[0054] Halogen atoms represented by R7 in compounds of the invention include fluorine, chlorine, bromine, or iodine atoms.

[0057] Aromatic groups represented by the group Ar1 and/or Ar2 in compounds of the invention include for example monocyclic or bicyclic fused ring C6-12 aromatic groups, such as phenyl, 1- or 2-naphthyl, 1- or 2-tetrahydronaphthyl, indanyl or indenyl groups. Aromatic groups represented by the group Ar2 may be optionally substituted by one, two, three or more R13 atoms or groups as defined below. Heteroaromatic groups represented by the group Ar1 and/or Ar2 in the compounds of formula (1) include for example C1-9 heteroaromatic groups containing for example one, two, three or four heteroatoms selected from oxygen, sulphur or nitrogen atoms. In general, the heteroaromatic groups may be for example monocyclic or bicyclic fused ring heteroaromatic groups. Monocyclic heteroaromatic groups include for example five- or six-membered heteroaromatic groups containing one, two, three or four heteroatoms selected from oxygen, sulphur or nitrogen atoms. Bicyclic heteroaromatic groups include for example eight- to thirteen-membered fused-ring heteroaromatic groups containing one, two or more heteroatoms selected from oxygen, sulphur or nitrogen atoms.

[0059] Optional substituents which may be present on the aromatic or heteroaromatic groups represented by Ar2 include one, two, three or more substituents, each selected from an atom or group R13 in which R13 is —R13a or —Alk4 (R13a)m, where R13a is a halogen atom, or an amino (—NH2), substituted amino, nitro, cyano, amidino, hydroxyl (—OH), substituted hydroxyl, formyl, carboxyl (—C02H), esterified carboxyl, thiol (—SH), substituted thiol, —COR 4, where R14 is an —Alk3(R13a)m, aryl or heteroaryl group, —CSR14, —SO3H, —SO2R14—SO2NH2, —SO2NHR14 SO2N(R4)2, —CONH2, —CSNH2, —CONHR4, —CSNHR14, —CON(R14)2, —CSN(R14)2, —N(R12 )SO2R14, —N(SO2R14)2, —NH2(R11) SO2NH2, —N(R)11)CSN(R14)2, —N(R11)SO2N(R14)2, —N(R11 )COR14, —N(R11)CON(R14)2, —N(R11)CSN(R14)2, CSN(R14)2, —N(R11)CSR14, —N(R11)C(O)OR14, —SO2 NHet1, where —NHet1 is an optionally substituted C5-7cyclicamino group optionally containing one or more other —O— or —S— atoms or —N(R11)—, —C(O)— or —C(S)-groups, —CONH et1, —CSNHet1, —N(R11)SO2NHet1, —N(R11)CONHet1,—N(R11)CSNHet1, —Het2, where Het2 is an optionally substituted monocyclic C5-7carbocyclic group optionally containing one or more —O— or —S—, atoms or —N(R11)—, —C(O)— or —C(S)— groups, —SO2N(R11)Het2, —CON(R11)Het2, —CSN(R11)Het2, —N(R11)CON(R11)Het2, —N(R11) CSN(R11)Het2, aryl or heteroaryl group; Alk4 is a straight or branched C1-6alkylene, C2-6alkenylene or C2-6alkynylene chain, optionally interrupted by one, two or three —O— or —S— atoms or —S(O)n, where n is an integer 1 or 2, or —N(R15)— groups, where R15 is a hydrogen atom or C1-6alkyl, e.g. methyl or ethyl group; and m is zero or an integer 1, 2 or 3. It will be appreciated that when two R11 or R14 groups are present in one of the above substituents, the R11 or R14 groups may be the same or different.

[0060] When in the group —Alk4(R13a)mm is an integer 1, 2 or 3, it is to be understood that the substituent or substituents R13a may be present on any suitable carbon atom in —Alk4. Where more than one R13a substituent is present these may be the same or different and may be present on the same or different atom in —Alk4. Clearly, when m is zero and no substituent R13a is present the alkylene, alkenylene or alkynylene chain represented by Alk4 becomes an alkyl alkenyl or alkynyl group.

[0061] When R13a is a substituted amino group it may be for example a group —NHR14, where R14 is as defined above, or a group —N(R14)2 wherein each R14 group is the same or different.

[0062] When R13a is a halogen atom it may be for example a fluorine, chlorine, bromine, or iodine atom.

[0063] When R13a is a substituted hydroxyl or substituted thiol group it may be for example a group —OR14 or a —SR14 or —SC(═NH)NH2 group respectively.

[0064] Esterified carboxyl groups represented by the group R13a include groups of formula —C02Alk5 wherein Alk5 is a straight or branched, optionally substituted C1-8alkyl group such as a methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, s-butyl or t-butyl group; a C6-12arylC1-8alkyl group such as an optionally substituted benzyl, phenylethyl, phenylpropyl, 1-naphthylmethyl or 2-naphthylmethyl group; a C6-12aryl group such as an optionally substituted phenyl, 1-naphthyl or 2-naphthyl group; a C6-12aryloxyC1-8 alkyl group such as an optionally substituted phenyloxymethyl, phenyloxyethyl, 1-naphthyl-oxymethyl, or 2-naphthyloxymethyl group; an optionally substituted C1-8alkanoyloxyC1-8alkyl group, such as a pivaloyloxymethyl, propionyloxyethyl or propionyloxypropyl group; or a C6-12aroyloxyC1-8alkyl group such as an optionally substituted benzoyloxyethyl or benzoyloxypropyl group. Optional substituents present on the Alk5 group include R13a substituents described above.

[0065] When Alk4 is present in or as a substituent it may be for example a methylene, ethylene, n-propylene, i-propylene, n-butylene, i-butylene, s-butylene, t-butylene, ethenylene, 2-propenylene, 2-butenylene, 3butenylene, ethynylene, 2-propynylene, 2-butynylene or 3-butynylene chain, optionally interrupted by one, two, or three —O— or —S—, atoms or —S(O)—, —S(O)2— or—N(R12)-groups.

[0066] Aryl or heteroaryl groups represented by the groups R13a or R14 include mono- or bicyclic optionally substituted C6-12 aromatic or C1-9 heteroaromatic groups as described above for the group Ar2. The aromatic and heteroaromatic groups may be attached to the remainder of the compound of formula (1) by any carbon or hetero e.g. nitrogen atom as appropriate.

[0067] When —NHet1 or —Het2 forms part of a substituent R13 each may be for example an optionally substituted pyrrolidinyl, pyrazolidinyl, piperazinyl, morpholinyl, thiomorpholinyl, piperidinyl or thiazolidinyl group. Additionally Het2 may represent for example, an optionally substituted cyclopentyl or cyclohexyl group. Optional substituents which may be present on —NHet1 or —Het2 include those R7 substituents described above.

[0069] Where desired, two R13 substituents may be linked together to form a cyclic group such as a cyclic ether, e.g. a C1-6alkylenedioxy group such as methylenedioxy or ethylenedioxy.

[0070] It will be appreciated that where two or more R13 substituents are present, these need not necessarily be the same atoms and/or groups. In general,the substituent(s) may be present at any available ring position in the aromatic or heteroaromatic group represented by Ar2.

[0071] The presence of certain substituents in the compounds of formula (1) may enable salts of the compounds to be formed. Suitable salts include pharmaceutically acceptable salts, for example acid addition salts derived from-inorganic or organic acids, and salts derived from inorganic and organic bases.

[0073] Salts derived from inorganic or organic bases include alkali metal salts such as sodium or potassium salts, alkaline earth metal salts such as magnesium or calcium salts, and organic amine salts such as morpholine, piperidine, dimethylamine or diethylamine salts.

[0075] One particular class of compounds of formula (1) is that wherein g is zero.

[0076] In the compounds according to the invention the group Ar1 is preferably a phenyl or monocyclic heteroaromatic group. Particularly useful groups of this type are five- or six-membered heteroaromatic groups as described previously, especially five- or six-membered heteroaromatic groups containing one or two heteroatoms selected from oxygen, sulphur or nitrogen atoms. Nitrogen-containing groups are especially useful, particularly pyridyl or pyrimidinyl groups.

[0077] A particularly useful group of compounds according to the invention has the formula (2):

[0078] wherein R1 and R2, which may be the same or different is each an atom or group —L2(Alk3)L3(R7)u in which L2, Alk3, t, L3, R7 and u are as defined for formula (1) provided that R1 and R2 are not both hydrogen atoms; Alk1, Alk2, m, r, L1, R4, R5, R6, Ra, Ar2, B and R are as defined for formula (1); and the salts, solvates, hydrates and N-oxides thereof.

[0079] R1 and R2 in compounds of formula (2) and in general in compounds of formula (1) is each preferably as particularly described above for compounds of formula (1), other than a hydrogen atom. Particularly useful R1 and R2 substituents include halogen atoms, especially fluorine or chlorine atoms, or methyl, halomethyl, especially —CF3, —CHF2 or —CH2F, methoxy or halomethoxy, especially —OCF3, —OCHF2 or —OCH2F groups.

[0080] R3 in compounds of the invention is in particular a hydrogen atom.

[0081] R in the compounds of formulae (1) and (2) is preferably a —CO2H group.

[0082] When present, the aliphatic chain represented by Alk1 in compounds of formulae (1) and (2) is preferably a —CH2—chain.

[0083] In general in compounds of formulae (1) and (2) —(Alk1)rL1 is preferably —CH2O— or—CON(R11)—. A particularly useful group is —CONH—.

[0084] In compounds of formulae (1) and (2) m is preferably 1 and Alk2 is preferably —CH2—; g in these compounds is preferably zero.

[0085] R4 and R1 in the compounds of formulae (1) and (2) may be the same or different and is each preferably a hydrogen or halogen atom or an alkyl, alkoxy, hydroxy, nitro, cyano or —NR8R9 group.

[0086] R6 and Ra in the compounds of formulae (1) and (2) is each preferably a hydrogen atom.

[0087] Particularly useful classes of compounds according to the invention are those wherein Ar2 is an optionally substituted monocyclic aromatic or heteroaromatic group. One especially useful aromatic group when represented by Ar2 is phenyl. Especially useful heteroaromatic groups represented by Ar2 include optionally substituted monocyclic nitrogen-containing heteroaromatic groups, particularly optionally substituted pyridyl, pyrimidinyl, pyridazinyl and triazinyl groups. Where the group is a triazinyl group it is preferably a 1,3,5 triazine.

[0088] Optional substituents which may be present on preferred Ar2 aromatic or heteroaromatic groups include for example one or two substituents selected from those R13 substituents described above.

[0091] As used herein, the following terms have the following meanings unless more limited definitions are used:

[0092] As used herein, “alkyl” refers to alkyl groups preferably having from 1 to 10 carbon atoms and more preferably 1 to 6 carbon atoms. This term is exemplified by groups such as methyl, t-butyl, n-heptyl, octyl and the like.

[0094] “Alkoxy” refers to the group “alkyl-O—” which includes, by way of example, methoxy, ethoxy, n-propoxy, iso-propoxy, n-butoxy, tert-butoxy, sec-butoxy, n-pentoxy, n-hexoxy, 1,2-dimethylbutoxy, and the like.

[0095] “Substituted alkoxy” refers to the group “substituted alkyl-O—”.

[0096] “Alkenoxy” refers to the group “alkenyl-O—”.

[0097] “Substituted alkenoxy” refers to the group “substituted alkenyl-O—”.

[0103] “Alkenyl” refers to alkenyl group preferably having from 2 to 10 carbon atoms and more preferably 2 to 6 carbon atoms and having at least 1 and preferably from 1-2 sites of alkenyl unsaturation.

[0105] “Alkynyl” refers to alkynyl group preferably having from 2 to 10 carbon atoms and more preferably 3 to 6 carbon atoms and having at least 1 and preferably from 1-2 sites of alkynyl unsaturation.

[0118] “Amino carbonylamino” refers to the groups —NRC(O)NRR, —NRC(O)NR-alkyl, —NRC(O)NR-substituted alkyl, —NRC(O)NR-alkenyl, —NRC(O)NR-substituted alkenyl, —NRC(O)NR-alkynyl, —NRC(O)NR-substituted alkynyl, —NRC(O)NR-aryl, —NRC(O)NR-substituted aryl, —NRC(O)NR-cycloalkyl, —NRC(O)NR-substituted cycloalkyl, —NRC(O)NR-heteroaryl, and —NRC(O)NR-substituted heteroaryl,—NRC(O)NR-heterocyclic, and —NRC(O)NR-substituted heterocyclic where each R is independently hydrogen, alkyl or where each R is joined to form together with the nitrogen atom a heterocyclic or substituted heterocyclic ring as well as where one of the amino groups is blocked by conventional blocking groups such as Boc, Cbz, formyl, and the like and wherein alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl, substituted cycloalkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocyclic and substituted heterocyclic are as defined herein.

[0119] “Aminothiocarbonylamino” refers to the groups —NRC(S)NRR, —NRC(S)NR-alkyl, —NRC(S)NR-substituted alkyl, —NRC(S)NR-alkenyl,—NRC(S)NR-substituted alkenyl, —NRC(S)NR-alkynyl, —NRC(S)NR-substituted alkynyl, —NRC(S)NR-aryl, —NRC(S)NR-substituted aryl, —NRC(S)NR-cycloalkyl, —NRC(S)NR-substituted cycloalkyl, —NRC(S)NR-heteroaryl, and —NRC(S)NR-substituted heteroaryl, —NRC(S)NR-heterocyclic, and —NRC(S)NR-substituted heterocyclic where each R is independently hydrogen, alkyl or where each R is joined to form together with the nitrogen atom a heterocyclic or substituted heterocyclic ring as well as where one of the amino groups is blocked by conventional blocking groups such as Boc, Cbz, formyl, and the like and wherein alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, dycloalkyl, substituted cycloalkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocyclic and substituted heterocyclic are as defined herein.

[0120] “Amino sulfonylamino” refers to the groups —NRSO2NRR, —NRSO2NR-alkyl, —NRSO2NR-substituted alkyl, —NRSO2NR-alkenyl, —NRSO2NR-substituted alkenyl, —NRSO2NR-alkynyl, —NRSO2NR-substituted alkynyl, —NRSO2NR-aryl, —NRSO2NR-substituted aryl, —NRSO2NR-cycloalkyl, —NRSO2NR-substituted cycloalkyl, —NRSO2NR-heteroaryl, and —NRSO2NR-substituted heteroaryl, —NRSO2NR-heterocyclic, and —NRSO2NR-substituted heterocyclic, where each R is independently hydrogen, alkyl or where each R is joined to form together with the nitrogen atom a heterocyclic or substituted heterocyclic ring as well as where one of the amino groups is blocked by conventional blocking groups such as Boc, Cbz, formyl, and the like and wherein alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl, substituted cycloalkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocyclic and substituted heterocyclic are as defined herein.

[0121] “Aryl” or “Ar” refers to an unsaturated aromatic carbocyclic group of from 6 to 14 carbon atoms having a single ring (e.g., phenyl) or multiple condensed rings (e.g., naphthyl or anthryl) which condensed rings may or may not be aromatic (e.g., 2-benzoxazolinone, 2H-1,4-benzoxazin-3(4H)-one-7yl, and the like). Preferred aryls include phenyl and naphthyl.

[0127] “Cycloalkyl” refers to cyclic alkyl groups of from 3 to 8 carbon atoms having a single cyclic ring including, by way of example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclooctyl and the like. Excluded from this definition are muti-ring alkyl groups such as adamantanyl, etc.

[0128] “Cycloalkenyl” refers to cyclic alkenyl groups of from 3 to 8 carbon atoms having single or multiple unsaturation but which are not aromatic.

[0137] “Halo” or “halogen” refers to fluoro, chloro, bromo and iodo and preferably is either chloro or bromo.

[0138] “Heteroaryl” refers to an aromatic carbocyclic group of from 2 to 10 carbon atoms and 1 to 4 heteroatoms selected from oxygen, nitrogen and sulfur within the ring or oxides thereof. Such heteroaryl groups can have a single ring (e.g., pyridyl or furyl) or multiple condensed rings (e.g., indolizinyl or benzothienyl). Additionally, the heteroatoms of the heteroaryl group may be oxidized, i.e., to form pyridine N-oxides or 1,1-dioxo-1,2,5-thiadiazoles and the like. Preferred heteroaryls include pyridyl, pyrrolyl, indolyl, furyl, pyridazinyl, pyrimidinyl, pyrazinyl, 1-oxo-1,2,5-thiadiazolyl and 1,1-dioxo-1,2,5-thiadiazolyl. The term “heteroaryl having two nitrogen atoms in the heteroaryl ring” refers to a heteroaryl group having two, and only two, nitrogen atoms in the heteroaryl ring and optionally containing 1 or 2 other heteroatoms in the heteroaryl ring, such as oxygen or sulfur.

[0140] “Heteroaryloxy” refers to the group —O-heteroaryl and “substituted heteroaryloxy” refers to the group —O-substituted heteroaryl.

[0141] “Heterocycle” or “heterocyclic” refers to a saturated or unsaturated group having a single ring or multiple condensed rings, from 1 to 10 carbon atoms and from 1 to 4 hetero atoms selected from nitrogen, sulfur or oxygen within the ring wherein, in fused ring systems, one or more of the rings can be aryl or heteroaryl.

[0144] “Heterocyclyloxy” refers to the group —O-heterocyclic and “substituted heterocyclyloxy” refers to the group —O-substituted heterocyclic.

[0145] “Thiol” refers to the group —SH.

[0146] “Thioalkyl” refers to the groups —S-alkyl.

[0147] “Substituted thioalkyl” refers to the group —S-substituted alkyl.

[0148] “Thiocycloalkyl” refers to the groups —S-cycloalkyl.

[0149] “Substituted thiocycloalkyl” refers to the group —S-substituted cycloalkyl.

[0150] “Thioaryl” refers to the group —S-aryl and “substituted thioaryl” refers to the group —S-substituted aryl.

[0151] “Thioheteroaryl” refers to the group —S-heteroaryl and “substituted thioheteroaryl” refers to the group —S-substituted heteroaryl.

[0152] “Thioheterocyclic” refers to the group —S-heterocyclic and “substituted thioheterocyclic” refers to the group —S-substituted heterocyclic.

[0153] “Nitrogen containing heteroaryl” refers to a heteroary ring as defined above that contains at least one nitrogen atom in the ring. Such heteroaryl groups can have a single ring (e.g., pyridyl) or multiple condensed rings (e.g., indolizinyl). Additionally, the heteroatoms of the heteroaryl group may be oxidized, i.e., to form pyridine N-oxides or 1, 1-dioxo-1,2,5-thiadiazoles and the like. Preferred nitrogen containing heteroaryls include pyridyl, pyrrolyl, indolyl, pyridazinyl, pyrimidinyl, pyrazinyl, 1-oxo-1,2,5-thiadiazolyl and 1,1-dioxo-1,2,5-thiadiazolyl. The term “heteroaryl having two nitrogen atoms in the heteroaryl ring” refers to a heteroaryl group having two, and only two, nitrogen atoms in the heteroaryl ring and optionally containing 1 or 2 other heteroatoms in the heteroaryl ring, such as oxygen or sulfur.

[0155] “Pharmaceutically acceptable salt” refers to pharmaceutically acceptable salts of a compound of Formula I which salts are derived from a variety of organic and inorganic counter ions well known in the art and include, by way of example only, sodium, potassium, calcium, magnesium, ammonium, tetraalkylammonium, and the like; and when the molecule contains a basic functionality, salts of organic or inorganic acids, such as hydrochloride, hydrobromide, tartrate, mesylate, acetate, maleate, oxalate and the like.

[0156] The compounds of this invention can be prepared in the manner described below using procedures known in the art and disclosed, for example, in U.S. patent application Ser. No.09/489,377 and WO 00/18759 both of which are incorporated herein by reference in its entirety.

[0157] Compounds according to the invention are potent and selective inhibitors of α4 integrins. The ability of the compounds to act in this way may be simply determined by employing tests such as those described in the Examples hereinafter.

[0158] The compounds are of use in modulating cell adhesion and in particular are of use in the prophylaxis and treatment of diseases or disorders involving inflammation in which the extravasation of leukocytes plays a role and the invention extends to such a use and to the use of the compounds for the manufacture of a medicament for treating such diseases or disorders.

[0159] Diseases or disorders of this type include inflammatory arthritis such as rheumatoid arthritis vasculitis or polydermatomyositis, multiple sclerosis, allograft rejection, diabetes, inflammatory dermatoses such as psoriasis or dermatitis, asthma and inflammatory bowel disease.

[0160] For the prophylaxis or treatment of disease the compounds according to the invention may be administered as pharmaceutical compositions, and according to a further aspect of the invention we provide a pharmaceutical composition which comprises a compound of formula (1) together with one or more pharmaceutically acceptable carriers, excipients or diluents.

[0161] Pharmaceutical compositions according to the invention may take a form suitable for oral, buccal, parenteral, nasal, topical or rectal administration, or a form suitable for administration by inhalation or insufflation.

[0162] For oral administration, the pharmaceutical compositions may take the form of, for example, tablets, lozenges or capsules prepared by conventional means with pharmaceutically acceptable excipients such as binding agents (e.g. pregelatinised maize starch, polyvinylpyrrolidone or hydroxypropyl methylcellulose); fillers (e.g. lactose, microcrystalline cellulose or calcium hydrogen phosphate); lubricants (e.g. magnesium stearate, talc or silica); disintegrants (e.g. potato starch or sodium glycollate); or wetting agents (e.g. sodium lauryl sulphate). The tablets may be coated by methods well known in the art. Liquid preparations for oral administration may take the form of, for example, solutions, syrups or suspensions, or they may be presented as a dry product for constitution with water or other suitable vehicle before use. Such liquid preparations may be prepared by conventional means with pharmaceutically acceptable additives such as suspending agents, emulsifying agents, non-aqueous vehicles and preservatives. The preparations may also contain buffer salts, flavouring, colouring and sweetening agents as appropriate.

[0163] Preparations for oral administration may be suitably formulated to give controlled release of the active compound.

[0164] For buccal administration the compositions may take the form of tablets or lozenges formulated in conventional manner.

[0165] The compounds for formula (1) may be formulated for parenteral administration by injection e.g. by bolus injection or infusion. Formulations for injection may be presented in unit dosage form, e.g. in glass ampoule or multi dose containers, e.g. glass vials. The compositions for injection may take such forms as suspensions, solutions or emulsions in oily or aqueous vehicles, and may contain formulatory agents such as suspending, stabilising, preserving and/or dispersing agents. Alternatively, the active ingredient may be in powder form for constitution with a suitable vehicle, e.g. sterile pyrogen-free water, before use.

[0166] In addition to the formulations described above, the compounds of formula (1) may also be formulated as a depot preparation. Such long acting formulations may be administered by implantation or by intramuscular injection.

[0167] For nasal administration or administration by inhalation, the compounds for use according to the present invention are conveniently delivered in the form of an aerosol spray presentation for pressurised packs or a nebuliser, with the use of suitable propellant, e.g. dichlorodifluoromethane, trichloro fluoromethane, dichlorotetrafluoroethane, carbon dioxide or other suitable gas or mixture of gases.

[0168] The compositions may, if desired, be presented in a pack or dispenser device which may contain one or more unit dosage forms containing the active ingredient. The pack or dispensing device may be accompanied by instructions for administration.

[0169] The quantity of a compound of the invention required for the prophylaxis or treatment of a particular condition will vary depending on the compound chosen, and the condition of the patient to be treated. In general, however, daily dosages may range from around 100 ng/kg to 100 mg/kg e.g. around 0.01 mg/kg to 40 mg/kg body weight for oral or buccal administration, from around 10 ng/kg to 50 mg/kg body weight for parenteral administration and around 0.05 mg to around 1000 mg e.g. around 0.5 mg to around 1000 mg for nasal administration or administration by inhalation or insufflation.

[0170] The compounds of the invention may be prepared by a number of processes as generally described below and more specifically in the Examples hereinafter. In the following process description, the symbols R1-R6, Ar1, L1, Alk1, Alk2, m, r, g, Ar2, Ra and R when used in the formulae depicted are to be understood to represent those groups described above in relation to formula (1) unless otherwise indicated. In the reactions described below, it may be necessary to protect reactive functional groups, for example hydroxy, amino, thio or carboxy groups, where these are desired in the final product, to avoid their unwanted participation in the reactions. Conventional protecting groups may be used in accordance with standard practice [see, for example, Green, T. W. in “Protective Groups in Organic Synthesis”, John Wiley and Sons, 1991]. In some instances, deprotection may be the final step in the synthesis of a compound of formula (1) and the processes according to the invention described hereinafter are to be understood to extend to such removal of protecting groups. For convenience the processes described below all refer to a preparation of a compound of formula (1) but clearly the description applies equally to the preparation of compounds of formula (2).

[0171] Thus according to a further aspect of the invention, a compound of formula (1) in which R is a —CO2H group may be obtained by hydrolysis of an ester of formula (3):

[0172] where Rb is an alkyl group, for example a C1-6alkyl group as described above.,

[0173] The hydrolysis may be performed using either an acid or a base depending on the nature of Rb, for example an organic acid such as trifluoroacetic acid or an inorganic base such as lithium or potassium hydroxide optionally in an aqueous organic solvent such as an amide, e.g. a substituted amide such as dimethylformamide, an ether, e.g. a cyclic ether such as tetrahydrofuran or dioxane or an alcohol, e.g. methanol at around ambient temperature. Where desired, mixtures of such solvents may be used.

[0174] Esters of formula (3) may be prepared by coupling an amine of formula (4)

[0175] or a salt thereof with a reagent Ar2X1 where X1 is a leaving group. Particular leaving groups represented by X1 include for example halogen atoms such as fluorine, chlorine or bromine atoms or sulphonyloxy groups such as a methylsulphonyloxy group.

[0176] The coupling reaction may be performed using standard conditions for reactions of this type. Thus for example the reaction may be carried out in a solvent, for example an alcohol, e.g. methanol or ethanol, at a temperature from around ambient to the reflex temperature, optionally in the presence of a base, e.g. an organic base such as an amine, e.g. triethylamine or N,N-diisopropylethylamine, or a cyclic amine, such as N-methylmorpholine or pyridine.

[0177] In a further example compounds of formula (4) [Ra, R6 are H, g is zero] can be converted into compounds of formula (5) by treatment with nitrous acid, or isoamyl nitrite in the presence of an acid source, for example acetic acid, in a halogenated hydrocarbon e.g. dichloromethane or chloroform at a temperature from ambient temperature to 60° C.

[0178] Esters of formula (3) can be obtained from diazo compounds of formula (5) by reaction with amines of formula Ar2RaNH optionally in the presence of a catalyst, for example a rhodium (II) catalyst, for example rhodium (II) acetate dimer, a copper (II) catalyst, for example copper (II) acetate or a palladium (II) catalyst, for example palladium (II) acetate in an organic solvent, e.g. toluene, at a temperature from around ambient to the reflex temperature.

[0179] Where desired, compounds of formula (4) may be linked to a suitable solid support, for example via their carboxylate group (Rb is H), and subsequently converted to compounds of formula (1) linked to the solid support via the methods just described. Displacement from the resin by any convenient method for example by cleavage using an acid such as trifluoroacetic acid, then gives the desired compound of formula (1).

[0180] Particular examples of such solid-phase syntheses are given in the Examples herein.

[0181] The amines of formula (4) may be obtained from simpler, known compounds by one or more standard synthetic methods employing C—C bond formation substitution, 1,4-addition, oxidation, reduction or cleavage reactions. Particular C—C bond forming reactions include the Horner-Emmons and Wittig reactions. Particular substitution approaches include conventional alkylation, arylation, heteroarylation, acylation, thioacylation, halogenation, sulphonylation, nitration, formylation and coupling procedures. It will be appreciated that these methods may also be used to obtain or modify other compounds of formulae (1) and (2) where appropriate functional groups exist in these compounds. Additionally, although a number of the intermediates Ar2X1 for use in the coupling reaction described above are known, others can be derived therefrom using these standard synthetic methods.

[0182] Thus compounds of the invention and intermediates thereto may be prepared by alkylation, arylation or heteroarylation. For example, compounds containing a —L1 H, —L2H, or —L3H group (where L1, L2 and L 3 is each a linker atom or group) may be treated with an alkylating agent:

[0183] ,(R7) uL3Alk3tX2 or R7aX2 respectively in which X2 is a leaving atom or group such as a halogen atom, e.g. a fluorine, bromine, iodine or chlorine atom or a sulphonyloxy group such as an alkylsulphonyloxy, e.g. trifluoromethylsulphonyloxy or arylsulphonyloxy, e.g. P-toluenesulphonyloxy group, and R7a is an alkyl group.

[0184] The reaction may be carried out in the presence of a base such as a Carbonate, e.g. caesium or potassium carbonate, an alkoxide, e.g. potassium t-butoxide, or a hydride, e.g. sodium hydride, in a dipolar aprotic solvent such as an amide, e.g. a substituted amide such as dimethylformamide or an ether, e.g. a cyclic ether such as (tetrahydrofuran).

[0185] In another example, compounds containing a —L1H, —L2H or —L3H group as defined above may be functionalised by acylation or thioacylation, for example by reaction with one of the alkylating agents just described but in which X2 is replaced by a —C(O)X3, C(S)X3, —N(R8) COX3 or —N(R8)C(S)X3 group in which X3 is a leaving atom or group as described for X2. The reaction may be performed in the presence of a base, such as a hydride, e.g. sodium hydride or an amine, e.g. triethylamine or N-methylmorpholine, in a solvent such as a halogenated hydrocarbon, e.g. dichloromethane or carbon tetrachloride or an amide, e.g. dimethylformamide, at for example ambient temperature. Alternatively, the acylation or thioacylation may be carried out under the same conditions with an acid or thioacid (for example one of the alkylating agents described above in which X2 is replaced by a —CO2H or —COSH group) in the presence of a condensing agent, for example a diimide such as 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide or N,N-dicyclohexylcarbodiimide, advantageously in the presence of a catalyst such as a N-hydroxy compound e.g. a N-hydroxytriazole such as 1-hydroxybenzotriazole. Alternatively the acid may be reacted with a chloroformate, for example ethylchloroformate, prior to the desired acylation reaction

[0186] In a further example compounds may be obtained by sulphonylation of a compound containing an —OH group by reaction with one of the above alkylating agents but in which X2 is replaced by a —S(O)Hal or —SO2Hal group in which Hal is a halogen atom such as chlorine atom] in the presence of a base, for example an inorganic base such as sodium hydride in a solvent such as an amide, e.g. a substituted amide such as dimethylformamide at for example ambient temperature.

[0187] In another example, compounds containing a —L1H, —L2H or —L3H group as defined above may be coupled with one of the alkylation agents just described but in which X2 is replaced by an —OH group in a solvent such as tetrahydrofuran in the presence of a phosphine, e.g. triphenylphosphine and an activator such as diethyl, diisopropyl- or dimethylazodicarboxylate.

[0188] In a further example, ester groups —CO2R8 or —CO2Alk5 in the compounds may be converted to the corresponding acid (—CO2H) by acid- or base-catalysed hydrolysis depending on the nature of the groups R8 or Alk5. Acid- or base-catalysed hydrolysis may be achieved for example by treatment with an organic or inorganic acid, e.g. trifluoroacetic acid in an aqueous solvent or a mineral acid such as hydrochloric acid in a solvent such as dioxan or an alkali metal hydroxide, e.g. lithium hydroxide in an aqueous alcohol, e.g. aqueous methanol.

[0189] In a further example, —OR8 or —OR14 groups, where R8 or R14 each represents an alkyl group such as methyl group, in compounds of formula (1) may be cleaved to the corresponding alcohol —OH by reaction with boron tribromide in a solvent such as a halogenated hydrocarbon, e.g. dichloromethane at a low temperature, e.g. around −78° C.

[0190] Alcohol [—OH] groups may also be obtained by hydrogenation of a corresponding —OCH2 R14 group, where R14 is an aryl group, using a metal catalyst, for example palladium on a support such as carbon in a solvent such as ethanol in the presence of ammonium formate, cyclohexadiene or hydrogen, from around ambient to the reflux temperature. In another example, —OH groups may be generated from the corresponding ester (—CO2Alk5 or CO2R8) or aldehyde (—CHO) by reduction, using for example a complex metal hydride such as lithium aluminium hydride or sodium borohydride in a solvent such as methanol.

[0191] In another example, alcohol —OH groups in the compounds may be converted to a corresponding —OR8 group by coupling with a reagent R8OH in a solvent such as tetrahydrofuran in the presence of a phosphine, e.g. triphenylphosphine and, an activator such as diethyl-, diisopropyl-, or dimethylazodicarboxylate.

[0192] Aminosulphonylamino (—NHSO2NH2) groups in the compounds may be obtained, in another example, by reaction of a corresponding amine (—NH2) with sulphamide in the presence of an organic base such as pyridine at an elevated temperature, e.g. the reflux temperature.

[0193] In a further example amine (—NH2) groups may be alkylated using a reductive alkylation process employing an aldehyde and a borohydride, for example sodium triacetoxyborohyride or sodium cyanoborohydride, in a solvent such as a halogenated hydrocarbon, e.g. dichloromethane, a ketone such as acetone, or an alcohol, e.g. ethanol, where necessary in the presence of an acid such as acetic acid at around ambient temperature.

[0194] In a further example, amine (—NH2) groups in compounds of formula (1) may be obtained by hydrolysis from a corresponding imide by reaction with hydrazine in a solvent such as an alcohol, e.g. ethanol at ambient temperature.

[0195] In another example, a nitro (—NO2) group may be reduced to an amine (—NH2), for example by catalytic hydrogenation using for example hydrogen in the presence of a metal catalyst, for example palladium on a support such as carbon in a solvent such as an ether, e.g. tetrahydrofuran or an alcohol e.g. methanol, or by chemical reduction using for example a metal, e.g. tin or iron, in the presence of an acid such as hydrochloric acid.

[0196] Aromatic halogen substituents in the compounds may be subjected to halogen-metal exchange with a base, for example a lithium base such as n-butyl or t-butyl lithium, optionally at a low temperature, e.g. around −78° C. in a solvent such as tetrahydrofuran and then quenched with an electrophile to introduce a desired substituent. Thus, for example, a formyl group may be introduced by using dimethylformamide as the electrophile; a thiomethyl group may be introduced by using dimethyldisulphide as the electrophile.

[0197] In another example, sulphur atoms in the compounds, for example when present in a linker group L1, L2 or L3 may be oxidised to the corresponding sulphoxide or sulphone using an oxidizing agent such as a peroxy acid, e.g. 3-chloroperoxybenzoic acid, in an inert solvent such as a halogenated hydrocarbon, e.g. dichloromethane, at around ambient temperature.

[0198] N-oxides of compounds of formula (1) may be prepared for example by oxidation of the corresponding nitrogen base using an oxidising agent such as hydrogen peroxide in the presence of an acid such as acetic acid, at an elevated temperature, for example around 70° C. to 80° C., or alternatively by reaction with a peracid such as peracetic acid in a solvent, e.g. dichloromethane, at ambient temperature.

[0199] Salts of compounds of formula (1) may be prepared by reaction of a compound of formula (1) with an appropriate base in a suitable solvent or mixture of solvents e.g. an organic solvent such as an ether e.g. diethylether, or an alcohol, e.g. ethanol using conventional procedures.

[0200] Where it is desired to obtain a particular enantiomer of a compound of formula (1) this may be produce d from a corresponding mixture of enantiomers using any suitable conventional procedure for resolving enantiomers.

[0201] Thus for example diastereomeric derivatives, e.g. salts, may be produced by reaction of a mixture of enantiomers of formula (1) e.g. a racemate, and an appropriate chiral compound, e.g. a chiral base. The diastereomers may then be separated by any convenient means, for example by crystallization and the desired enantiomer recovered, e.g. by treatment with an acid in the instance where the diastereomer is a salt.

[0202] In another resolution process a racemate of formula (1) may be separated using chiral High Performance Liquid Chromatography. Alternatively, if desired a particular enantiomer may be obtained by using an appropriate chiral intermediate in one of the processes described above.

[0203] Chromatography, recrystallization and other conventional separation procedures may also be used with intermediates or final products where it is desired to obtain a particular geometric isomer of the invention.

[0204] The following examples illustrate synthetic methods which could be used in the methods of this invention by merely replacing a nitrogen containing heteroaryl reagent with the phenyl reagents used therein. All temperatures are in ° C. The following abbreviations are used:

[0205] MeOH—methanol;

[0206] BOC—butoxycarbonyl;

[0207] DCM—dichloromethane;

[0208] AcOH—acetic acid;

[0209] DIPEA—N,N-diisopropylethylamine;

[0210] DMF—dimethylformamide;

[0211] LDA—lithium N,N-diisopropylamide;

[0212] mCPBA—3-chloroperoxybenzoic acid

[0213] All NMR's were obtained at 300 mHz.

INTERMEDIATE 1 3,5-Dichloropyridine-4-carboxylic acid

[0214] A solution of 3,5-dichloropyridine (5.00 g, 33.8 mmol) in THF (25 ml) was added to a solution of LDA [generated from nBuLi (2.5 M solution hexanes, 14.9 ml, 37.2 mmol) and diisopropylamine (4.10 g, 5.7 ml, 40.6 mmol)] in THF (25 ml) at −78° then CO2 gas was bubbled through to give a clear brown solution that slowly gave a precipitate, warmed to room temperature over 2 h, then quenched with water (20 ml) and partitioned between diethylether (100 ml) and 1M NaOH (100 ml). The aqueous layer was separated and acidified to pH1 with concentrated hydrochloric acid and then extracted with 10% MeOH in DCM (100 ml×3). The combined organic layers were dried (MgSO4) and the solvent removed in vacuo to give a brown solid that was recrystallized from ethanol and dried under vacuum to give the title compound as pinkish crystals (2.63 g, 41%): δH (DMSO d6) 8.72 (2H, s).

[0238] A portion of Intermediate 24 (3.0 g) was treated twice with a 20% solution of piperidine in DMF (100 ml), once for 5 min and once for 15 min. The resin was washed with DMF, methanol and DCM. This material was treated with isoamyl nitrite (1.79 ml, 12.30 mmols) and acetic acid (0.074 ml, 1.23 mmols) in anhydrous chloroform (70 ml) for 1 hr, then filtered and washed with DMF, methanol and DCM then finally air dried to give the title compound.

[0356] A mixture of Intermediate 25 (150 mg), dirhodiumtetraacetate, (1.8 mg, 5.1 μmols) and 2-amino-6-propylpyridine in annydrous toluene (2.5 mL) was agitated at ambient temperature for 0.5 h then at 80° C. for 6 h. The resin was filtered and then washed with DCM, DMF, methanol, water, methanol, DMF and DCM. The resin was treated with 50% trifluoroacetic acid in DCM (4. Oml) for 3 h with agitation and filtered. The resin was then washed with a 4. Oml portion of DCM. The combined filtrate was evaporated in vacuo to give the crude product (48 mg) which was purified by preparative HPLC to afford the title compound (2.7 mg). HPLC-MS Retention time 2.19 min; MH+473.

[0357] HPLC-MS

[0358] HPLC-MS was performed on a Hewlett Packard 1100/MSD ES Single Quadropole system with diode array detector using a Luna C18(2) 50×2. Omm (3 μm) column, running a gradient of 95% [0.1% aqueous formic acid], 5% [0.1% formic acid in acetonitrile] to 10% [0.1% aqueous formic acid], 90% [0.1% formic acid in acetonitrile] over 2 min, then maintaining the mobile phase at that ratio for a further 1 min. Flow rate 0.8 ml/min. MS was acquired by API electrospray in positive ion mode, at 70V, scanning from 150 to 750 amu.

[0359] The following compounds of Examples 118-168 were prepared in a similar manner to the compound of Example 117, each using the starting material shown in place of 2-amino-6-propylpyridine.

[0411] The following assays can be used to demonstrate the potency and selectivity of the compounds according to the invention. In each of these assays an IC50 value was determined for each test compound and represents the concentration of compound necessary to achieve 50% inhibition of cell adhesion where 100% =adhesion assessed in the absence of the test compound and 0%=absorbance in wells that did not receive cells.

[0412] α4β1Integrin-dependent Jurkat cell adhesion to VCAM-Iq

[0413] 96 well NUNC plates were coated with F(ab)2 fragment goat anti-human IgG Fcγ-specific antibody [Jackson Immuno Research 109-006-098: 100 μl at 2 μg/ml in 0.1M NaHCO3, pH 8.4], overnight at 4°. The plates were washed (3×) in phosphate-buffered saline (PBS) and then blocked for 1 h in PBS/1% BSA at room temperature on a rocking platform. After washing (3× in PBS) 9 ng/ml of purified 2d VCAM-Ig diluted in PBS/1% BSA was added and the plates left for 60 minutes at room temperature on a rocking platform. The plates were washed (3× in PBS) and the assay then performed at 37° for 30 min in a total volume of 200 μl containing 2.5×105 Jurkat cells in the presence or absence of titrated test compounds.

[0414] Each plate was washed (2×) with medium and the adherent cells were fixed with 100 μl methanol for 10 minutes followed by another wash. 100 μl 0.25% Rose Bengal (Sigma R4507) in PBS was added for 5 minutes at room temperature and the plates washed (3×) in PBS. 100 μl 50% (v/v) ethanol in PBS was added and the plates left for 60 min after which the absorbance (570 nm) was measured.

[0415] α4β7 Integrin-dependent JY cell adhesion to MAdCAM-Ig

[0416] This assay was performed in the same manner as the α4β1 assay except that MAdCAM-Ig (150 ng/ml) was used in place of 2d VCAM-Ig and a sub-line of the β-lympho blastoid cell-line JY was used in place of Jurkat cells. The IC50 value for each test compound was determined as described in the α4β1 integrin assay.

[0417] α5β1 Integrin-dependent K562 cell adhesion to fibronectin

[0418] 96 well tissue culture plates were coated with human plasma fibronectin (Sigma F0895) at 5 μg/ml in phosphate-buffered saline (PBS) for 2 hr at 37° C. The plates were washed (3× in PBS) and then blocked for 1 h in 100 μl PBS/1% BSA at room temperature on a rocking platform. The blocked plates were washed (3× in PBS) and the assay then performed at 37° C. in a total volume of 200 μl containing 2.5×105 K562 cells, phorbol-12-myristate-13-acetate at 10 ng/ml, and in the presence or absence of titrated test compounds. Incubation time was 30 minutes. Each plate was fixed and stained as described in the α4β1 assay above.

[0420] 96 well tissue culture plates were coated with RPMI 1640/10% FCS for 2 h at 37° C. 2×105 freshly isolated human venous polymorphonuclear neutrophils (PMN) were added to the wells in a total volume of 200 μl in the presence of 10 ng/ml phorbol-12-myristate-13-acetate, and in the presence or absence of test compounds, and incubated for 20 min at 37° C. followed by 30 min at room temperature. The plates were washed in medium and 100 μl 0.1% (w/v) HMB (hexadecyl trimethyl ammonium bromide, Sigma H5882) in 0.05M potassium phosphate buffer, pH 6.0 added to each well. The plates were then left on a rocker at room temperature for 60 min. Endogenous peroxidase activity was then assessed using tetramethyl benzidine (TMB) as follows: PMN lysate samples mixed with 0.22% H2O2 (Sigma) and 50 μg/ml TMB (Boehringer Mannheim) in 0.1M sodium acetate/citrate buffer, pH 6.0 and absorbance measured at 630 nm.

[0423] In the above assays the preferred compounds of the invention generally have IC50 values in the α4β1 and α4β7 assays of 1 μM and below. In the other assays featuring a integrins of other subgroups the same compounds had IC50 values of 50 μM and above thus demonstrating the potency and selectivity of their action against α4 integrins.